A cyberattack has disrupted hospitals and health care in several states

Hospitals and clinics in several states on Friday began the time-consuming process of recovering from a cyberattack that disrupted their computer systems, forcing some emergency rooms to shut down and ambulances to be diverted.

Hospitals and clinics in several states on Friday began the time-consuming process of recovering from a cyberattack that disrupted their computer systems, forcing some emergency rooms to shut down and ambulances to be diverted.

Many primary care services at facilities run by Prospect Medical Holdings remained closed on Friday as security experts worked to determine the extent of the problem and resolve it.

John Riggi, the American Hospital Association's national advisory for cybersecurity and risk, said the recovery process can often take weeks, with hospitals in the meantime reverting to paper systems and humans to do things such as monitor equipment and run records between departments.

"These are threat-to-life crimes, which risk not only the safety of the patients within the hospital, but also risk the safety of the entire community that depends on the availability of that emergency department to be there," Riggi said.

The latest "data security incident" began Thursday at facilities operated by Prospect, which is based in California and has hospitals and clinics there and in Texas, Connecticut, Rhode Island and Pennsylvania.

"Upon learning of this, we took our systems offline to protect them and launched an investigation with the help of third-party cybersecurity specialists," the company said in a statement Friday. "While our investigation continues, we are focused on addressing the pressing needs of our patients as we work diligently to return to normal operations as quickly as possible."

The White House has been monitoring the cyberattack, said Adrienne Watson, a spokesperson for the National Security Council.